What tree species are best for carbon sequestration?

Question

Fast-growing, long-lived, maintenance needs --

Which species can sequester the most carbon most quickly, and which can hold the carbon for the longest period of time?

Answer 1

Location is the most important factor.

Trees growing near the equator grow fast, and year round.  Trees toward the poles grow very slowly.  The worst is evergreens in cold climates, which, by blocking reflective snow, can actually be a net loss.

People who link saving the rain forest and global warming, are right.  A seemingly mediocre tree in a tropical climate can be better than the best tree in a temperate climate.

The point about early growth being faster and better is also a good one.  The bottom line is that a number of factors must be taken into account, and focusing on species in isolation is unlikely to be a good idea.

Answer 2

I apologize this is one of those moot questions...interesting though. Has anybody stopped to think, what just one shade tree planted on the south side of a home will do for energy savings, emissions...etc? The (deciduous) type, I always like that word.  The US has a net C sink of~15% there is an uncertainty that any ecologcial transition would have much of a effect. *(JS). Of course the Rain Forest represent something all together different. From what I've heard there is a problem with old-vs-new growth.

You remind me of somebody...(Clestine Sibbly)*sp, wrote a nature column for the AJC and a few books. "Darn I wish I could recollect the spelling."

Answer 3

Depends on where you are and if you have an end use.  Lumber, for example decomposes about 1/4 inch in 100 years, a southern pine forest will grow vigorously for 30 or 40 years  in the south sequestering CO2, then will become a source as it reaches maturity.  It may take 300 years in the US west for a Douglas fir forest to finish the same cycle. We need a mix of forest to sequester as much CO2 as possible.  This won't be enough alone to meet CO2 reduction goals and remember, the ocean has much more plant-life than terrestrial systems.

An important thing to remember is we need to remove enough fiber from forests to make sure they continuously grow vigorously, otherwise the become sources of CO2 when they approach maturity. The fiber harvested has to be be used in some way that slows down decomposition or it releases the CO2 sequestered.

Answer 4

That turns out to be a fascinating topic.  Forest sequestration turns out to be less effective than hoped beyond the iniitial growth spurt during reforestation, as forests reach equilibrium, with slower growth rates and the carbon benefits of growth offset by negative impacts such as decay and fires.

Trees may not help relieve global warming effects

http://www.usatoday.com/news/science/cli...

Experiments conducted in a North Carolina pine forest show that after an initial growth spurt, trees grow more slowly and do not absorb as much excess carbon from the atmosphere as expected. The results suggest that planting trees may not thwart global warming or serve as an adequate substitute for reducing heat-trapping greenhouse gas emissions.

Because their trees are old and slow-growing, the Amazon forests, which contain about a third of all carbon found in land vegetation, have less capacity to absorb atmospheric carbon than previous studies have predicted. Although some of the largest trees also grow the fastest and can take up carbon quickly, the vast majority of the Amazon trees grow slowly.

Amazon Trees Much Older Than Assumed, Raising Questions On Global Climate Impact Of Region

http://www.sciencedaily.com/releases/200...

“In the Central Amazon, where we found the slowest growing trees, the rates of carbon uptake are roughly half what is predicted by current global carbon cycle models,” Trumbore said. “As a result, those models – which are used by scientists to understand how carbon flows through the Earth system – may be overestimating the forests’ capacity to remove carbon dioxide from the atmosphere.”

“In addition, the impact of logging activity in the Amazon region may be longer-lasting than we think,” Trumbore added, “because it may take centuries for these forests to grow back to their full size.”

http://www.epa.gov/sequestration/faq.htm...

Pine plantations in the Southeast can accumulate almost 100 metric tons of carbon per acre after 90 years, or roughly one metric ton of carbon per acre per year (Birdsey 1996). Changes in forest management (e.g., lengthening the harvest-regeneration cycle) generally result in less carbon sequestration on a per acre basis. Changes in cropping practices, such as from conventional to conservation tillage, have been shown to sequester about 0.1 – 0.3 metric tons of carbon per acre per year (Lal et al. 1999; West and Post 2002). However, a more comprehensive picture of the climate effects of these practices needs to also consider possible nitrous oxide (N2O) and methane (CH4) emissions. (See also FAQ #8)

http://www.epa.gov/sequestration/faq.htm...

Carbon accumulation in forests and soils eventually reaches a saturation point, beyond which additional sequestration is no longer possible. This happens, for example, when trees reach maturity, or when the organic matter in soils builds back up to original levels before losses occurred. Even after saturation, the trees or agricultural practices would need to be sustained to maintain the accumulated carbon and prevent subsequent losses of carbon back to the atmosphere.

Do sequestration practices affect greenhouse gases other than CO2?

http://www.epa.gov/sequestration/faq.htm...

Yes. Methane (CH4) and nitrous oxide (N2O) are potent greenhouse gases that are also important to consider for forests, croplands and grazing lands. Practices that maintain and sequester carbon can have both positive and negative effects on CH4 and N2O emissions. The relationship among practices that affect CO2, CH4, and N2O can be especially complex in cropping and grazing systems. For example, if nitrogen-based fertilizers are applied to crops to increase yields, this would likely enhance soil carbon but the benefit could be partially or completely offset by increased emissions of N2O. The practice of rotational grazing can be beneficial across all three major gases: soil carbon can be maintained and enhanced; livestock CH4 emissions should decline due to improved forage quality; and N2O emissions can be avoided by eliminating the need for fertilizer applications on the pasture. These complex interactions among gases mean that it is important to consider not only carbon but all the greenhouse gas effects for certain sequestration practices.

How could carbon sequestration be affected by climate change?

http://www.epa.gov/sequestration/faq.htm...

In addition to temperature, human-induced climate change may also affect growing seasons, precipitation and the frequency and severity of extreme weather events, such as fire. These changes can influence forests, farming and the health of ecosystems, and thus carbon sequestration.

Current projections of business-as-usual U.S. sequestration rates under various climate change scenarios show both increases and decreases in carbon storage depending on various assumptions. To date, few analyses of the potential for additional sequestration over time have considered the future effects of climate change.

...do sequestration activities compare with greenhouse gas reductions in other sectors?

http://www.epa.gov/sequestration/faq.htm...

...the climate benefits of sequestration practices can be partially or completely reversed because terrestrial carbon can be released back to the atmosphere through decay or disturbances. Trees that sequester carbon are subject to natural disturbances and harvests, which could suddenly or gradually release the carbon back to the atmosphere. And if carbon sequestration practices in agriculture, such as reduced tillage, are abandoned or interrupted, most or all of the accumulated carbon can be quickly released. Some sequestration practices, like tree planting and improved soil management, also reach a point where additional carbon accumulation is no longer possible. For example, mature forests will not sequester additional carbon after the trees have fully grown. At this point, however, the mature trees or practices still need to be sustained to maintain the level of accumulated carbon. Addressing the issues of reversibility (or duration) and carbon saturation is important if sequestration benefits are to be compared to other greenhouse gas reductions.

Answer 5

Wat is best in YOUR area is likely to be different from what grows best in MY geographic location.

In a cool moist area like where I live, a good choice would be the American sicomore tree.

Any fast growing tree will convert LOTS of CO2 into wood.

Long lived is not necessarily the best choice. Trees are most efficient early in life when they grow quickly. Then they should be cut down and the wood used for some use that will permanently lock that carbon up so it won't be returned to the atmosphere.

Building houses, using it for paper that won't easily or quickly decay, ......

Build bridges. Wood can be treated to resist decay, insect infestation, chemical resistance, etc. It is more durable than concrete and steel. Using concrete for construction and processing of steel both require the production of a lot of CO2

Answer 6

As a geologist, I guess I was trained to think in time intervals beyond the trees life.  I don't think you are going to have much of a net sequestration unless you actually remove the organic compounds and store them in some way.  For example, If you took trees and buried them in some high dry place. Even then the carbon would probably get released in a few thousand years.

Answer 7

It is not just trees but all plants that are green. A process of photosynthesis the plant takes in the CO2 and changes it to oxygen,the plant keeps the C to make its food out of. The plants do not hold CO2 they recycle it. Later the plant leaves die and wash down the river to the deltas where it deteriorates into oil & gas. It is a complete cycle .

Answer 8

Discover what the fastest growing (in terms of adding mass) tree is and you'll have your answer.  Cottonwoods probably rank right up there.

Answer 9

Amy,

  

    Not sure if this is what your looking for, hope it helps.

Yellow poplars, scarlet oaks, London planes, or American sweetgums. All are fast-growing hardwoods that require little maintenance (and thus little use of gas-guzzling equipment), and have proved to be solid carbon absorbers in tests. According to a 2002 survey of several hundred New York City trees, a yellow poplar (also known as the tulip tree) was the carbon sequestration champion, socking away an impressive 137.26 pounds of carbon. (The runner-up, strangely, was a European beech, at 112.39 pounds.)